High brightness, halogen cycle incandescent lamps are well known in the art. Due to the intense heat which such lamps generate, their glass housing is generally made of a high-temperature, refractory material, such as quartz. Due to the difficulty of making an air-tight quartz-to-metal seal, the lead-in conductors are generally passed through a flat-shaped stem at the bottom and top of the lamp. Proper positioning of the lamp is then provided by a housing structure into which the stems are fitted.